String theory and Symmetry

Okay, underlying most physical objects in their mathematical structure is some kind of symmetry. Certain things have a very evident symmetry, others do not. But (according to the mathematics of Lie groups) we can use mapping to find the underlying symmetry. A Lie group is a mathematical set that has a smooth manifold (that is, it is sufficiently close to being Euclidean) and is continuously differentiable at each point. (Example of a smooth manifold is a globe of the Earth being constructed of sufficiently small flat maps. It’s close enough to being Euclidean, even though it is a sphere.) The Mathematician Sophus Lie discovered (invented) these groups which now bear his name. Why is this relevant, you ask? Of the varieties of groups that bear his name some have odd dimensionality. Recently, the group E8 was mapped (after a four-year project). E8 has 248 dimensions. I know this is difficult to grasp spatially, but hey, that’s what the mathematicians say. Again, why is this relevant? Well, in string theory the ugly infinities cannot be avoided in simple four dimensional space-time. The more recent advances in string theory suggest a structure with E8 X E8 symmetry. (I’m not sure if that means 61504 dimensions or not). Granted, mapping such a complex structure deserves proper acclaim, but two-hundred and forty-eight dimensions? How come string theory cannot tell us why two-hundred and forty-four of those dimensions are ‘rolled’ up so tight that only four are sensible, and of these four three are ’space-like’ and only one is ‘time-like’? Could it even explain a fifth dimension? What evidence is there for the non-sensible in the field of sensible physics? Is it only by the elegance of the mathematics?

Far from the final word on string theory, I offer you: